1. Field of the Invention
This invention relates generally to peanut processing equipment and more particularly is directed towards self-adjusting apparatus for use in slitting the skins of peanuts.
2. Description of the Prior Art
In many food products in which peanuts are used, the practice has been to employ blanched peanuts. A blanched peanut is one which has both its hard outer shell as well as its inner dark, reddish brown skin removed. Blanching refers to that part of the peanut process in which this inner dark skin is removed.
According to present practice, nut blanching may be carried out by first slitting the outer skin of the nuts substantially from one end to the other end and along both sides. After the skins have been slit in this fashion, they are then loosened by dousing the nuts in a bath of scalding water in a process known as water blanching, wherein the water-soaked nuts have their skins removed by passing the nuts between a pair of opposing, oscillating rubbing surfaces. Another process by which the dark skin is removed is through a dry blanching operation in which nuts skins are first slit and the nuts are then fed onto a moving belt which carries the nuts against a fixed abrasive baffle, causing the nuts to spin and the skins to be removed thereby. Blanching machines of the latter character are more fully described in U.S. Pat. Nos. 3,196,914 and 3,951,057. The equipment to slit the peanut skins without breaking or splitting the nuts is shown in U.S. Pat. Nos. 3,217,764 and 3,964,379. In these patents the slitting equipment has involved the use of a pair of upper and lower rollers mounted for rotation about horizontal parallel axes and which define a gap adapted through which each nut in a stream of nuts is fed. On either side of the gap are slitting elements in the form of blades which are spring-loaded and which form a slit in the nut skin from end to end of the nuts as they are fed through the bite of the rollers.
In view of the fact that peanuts vary in size, not only from one batch to another but also within the same batch, considerable care must be taken to maintain a proper gap size between the two rollers in order to prevent splitting the nuts from the pressure of the rollers if the gap is too small, or from loss of feed control in the event that the gap is made to large. Typically, the gap is set to the average size of the nuts being fed through the equipment at the start of each batch of nuts being processed. In U.S. Pat. No. 3,217,764 the gap between each pair of rolls was individually set for the average nut size while in U.S. Pat. No. 3,964,379 the gaps for several rolls in a single machine were set by operating a lever. In either event, the arrangement was not entirely satisfactory from the standpoint of the time and skill involved in adjusting each pair of rolls or each set of rolls in a particular machine. In practice, slitting machines of this type are provided in large numbers in a processing plant and a considerable amount of time is required to adjust each machine to a particular size. Even after the size has been set, the machines must be monitored on a regular basis because of possibility of clogging from oversized nuts trying to get through the rolls or nuts spilling off the rolls because they are undersized.
Accordingly, it is an object of the present invention to provide improvements in machines for slitting the skins of peanuts and the like.
Another object of this invention is to provide self-adjusting equipment for use in slitting the skins of peanuts and the like in a peanut blanching operation.